63613668491 has 4 divisors (see below), whose sum is σ = 63850150800. Its totient is φ = 63377186184.

The previous prime is 63613668473. The next prime is 63613668497. The reversal of 63613668491 is 19486631636.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-63613668491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (63613668497) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 118240751 + ... + 118241288.

It is an arithmetic number, because the mean of its divisors is an integer number (15962537700).

Almost surely, 2^63613668491 is an apocalyptic number.

63613668491 is a deficient number, since it is larger than the sum of its proper divisors (236482309).

63613668491 is a wasteful number, since it uses less digits than its factorization.

63613668491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 236482308.

The product of its digits is 3359232, while the sum is 53.

The spelling of 63613668491 in words is "sixty-three billion, six hundred thirteen million, six hundred sixty-eight thousand, four hundred ninety-one".